browser control - how to identify redirects and popups

First of all, I'd like to say thanks for the wealth of information on this site, great job guys!

Anyways, this is my current vex and I'd like any opinions as to whether this will work.

I had medium level exp in VB6 and have jumped in the deep end in .net so be gentle :) I mostly write PLC code so this is a bit of a sideline for me.

The app I'm writing is designed to monitor information on a predefined website. when it works, it works but I am trying to cover cases where the site can't be reached (either due to network problems or the site being unavailable). I had a case where the site was unavailable and my ISP's decided to open a popup survey :mad: and I'm trying to avoid this happening.

Most of the answers to what I'm trying to do, I got in this thread.

What I'm trying to add to the ping is to verify that the correct site responded and if not then don't send the browser.navigate command.

Here's the code I've come up with -
The Call:

Code:

---

        log("scan initiated; URL=" & address & "; ")
        If My.Computer.Network.IsAvailable Then
            If SiteIsAvailable(address) Then
                MyBrowser.Navigate(address)
            Else
                log("Error: Could not connect to site: " & address)
                MsgBox("Error: Could not connect to site: " & address, MsgBoxStyle.Exclamation, AcceptButton)
            End If

        Else
            log("Error: network not connected")
            MsgBox("Error: network not connected", MsgBoxStyle.Exclamation, AcceptButton)
        End If

---

The function:

Code:

---

Private Function SiteIsAvailable(ByVal SiteUrl As String) As Boolean
        'SiteUrl should be in the format "www.domain.ext"

        Dim urlTest As New System.Uri("http://" & SiteUrl)
        Dim wreqTest As WebRequest

        SiteIsAvailable = False 'just in case

        wreqTest = WebRequest.Create(urlTest)
        Dim wrespTest As System.Net.WebResponse
        Try
            wrespTest = wreqTest.GetResponse()
            wrespTest.Close()
            wreqTest = Nothing
            'Pass
            If wrespTest.ResponseUri.OriginalString = "http://" & SiteUrl Then
                SiteIsAvailable = True
            End If
        Catch ex As Exception
            wreqTest = Nothing
            log(ex.ToString)
            'Failed - GTFO, it doesn't exist or it's not the site it's supposed to be
        End Try
    End Function

---

What I'm wondering is if the "If wrespTest.ResponseUri.OriginalString = "http://" & SiteUrl Then" statement would reasonably be expected to identify when a re-direct has occurred to a search page?

Thanks in advance.